Management of Subarachnoid Hemorrhage

Initial Management

• Place an external ventricular drain (EVD) urgently if symptomatic hydrocephalus is present, as recommended by the American Heart Association 1
• Maintain EVD at appropriate height to target intracranial pressure (ICP) <20 mmHg, according to the Critical Care society 2
• Consider barbiturate therapy for refractory intracranial hypertension, as suggested by the American Heart Association 1
• Secure airway if GCS ≤8 or deteriorating neurological status, and follow with placement of nasogastric/orogastric tube to prevent aspiration, as recommended by the American Heart Association 1
• Maintain appropriate oxygenation without hyperventilation to prevent cerebral vasoconstriction and worsen cerebral ischemia, as recommended by the American Heart Association 1

Respiratory Management

• Avoid hyperventilation except for brief periods to manage acute ICP spikes, as recommended by the Critical Care society 2
• Maintain PaO₂ >80 mmHg to ensure adequate oxygenation, according to the Critical Care society 2
• Target normocapnia (PaCO₂ 35-40 mmHg), as recommended by the Critical Care society 2
• Brief periods of hypocapnia may be used for acute ICP spikes, but prolonged hypocapnia should be avoided as it may cause cerebral ischemia, according to the Critical Care society 2
• If ARDS develops, careful PEEP titration is required, with PEEP <15 cmH₂O generally safe early after SAH, as recommended by the Critical Care society 2
• Be cautious with PEEP in patients with elevated ICP, particularly during the peak vasospasm period (days 6-8), according to the Critical Care society 2

Medication Management

• Administer nimodipine 60 mg orally every 4 hours for 21 days to improve neurological outcomes, as recommended by the International Journal of Stroke society 3 and American Heart Association 4
• Use short-acting sedatives (propofol, dexmedetomidine) to reduce ICP if necessary, according to the Critical Care society 2
• Maintain blood pressure control with titratable agents to keep systolic BP <160 mmHg, as recommended by the American Heart Association 1, 5, 4

Surgical Management

• Consider surgical evacuation of hematoma if there is significant mass effect, as recommended by the International Journal of Stroke society 3
• Consider early aneurysm obliteration, ideally within 24 hours, to reduce mortality and improve neurological outcomes in patients with SAH, as recommended by the American Heart Association 4
• Treatment options for aneurysm obliteration include endovascular coiling and surgical clipping, and the decision between approaches should be made multidisciplinarily, as recommended by the American Stroke Association 5, 4
• The following grading systems can be used to assess the severity of SAH:

3, 4, 5, 1

• Hunt and Hess Grade predicts outcome in SAH patients, with a grading system as follows:

1, 4, 5

Monitoring and Prevention

• Continuous neurological assessment to detect deterioration, with transcranial Doppler to monitor for vasospasm, and regular electrolyte monitoring, particularly sodium levels, as recommended by the American Academy of Neurology and American Heart Association 6, 4, 5
• Maintain euvolemia and avoid hypovolemia/hypervolemia to prevent cerebral edema, and avoid using hypotonic fluids which may worsen cerebral edema, as recommended by the American Heart Association 4, 5
• Assess the level of consciousness using the Glasgow Coma Scale (GCS) in patients with suspected subarachnoid hemorrhage (SAH), as recommended by the American Heart Association 6
• Document symptoms such as sudden onset severe headache, nausea and vomiting, neck pain or stiffness, photophobia, and altered mental status in patients with SAH, as recommended by the American Heart Association 6, 1
• Venous thromboembolism prophylaxis should be initiated once the aneurysm is secured, as recommended by the American Heart Association 5
• Regular monitoring of serum sodium levels is essential to avoid large fluctuations in sodium levels, which can be associated with worse neurologic outcomes, as recommended by the American Heart Association 1

Diagnosis and Prognosis

• Non-contrast head CT should be performed; if negative but high clinical suspicion, a lumbar puncture should be done to confirm diagnosis 1, 4
• Vascular imaging, such as CT Angiography (CTA) or Digital Subtraction Angiography (DSA) with 3D rotational angiography, should be performed to identify aneurysm location, as recommended by the American Heart Association and American Stroke Association 1, 4, 5
• Misdiagnosis of aSAH is associated with a nearly 4-fold higher likelihood of death or disability at 1 year, with the most common diagnostic error being failure to obtain a noncontrast head CT scan, which has a sensitivity approaching 100% in the first 12 hours after hemorrhage, as recommended by the American Heart Association and American Stroke Association 1, 4, 5
• The case fatality rate after aneurysmal hemorrhage is approximately 50%, with one in eight patients dying outside the hospital, but outcome has improved over time with early intervention and aggressive management 7
• A sentinel or warning headache is a sudden, intense headache that precedes a major aneurysmal subarachnoid hemorrhage (aSAH) by days to weeks, representing a minor hemorrhage or "warning leak" from an intracranial aneurysm that signals impending catastrophic rupture, occurring in 10-43% of patients, typically 2-8 weeks before overt aSAH, and may persist for several days with associated nausea and vomiting, but uncommon meningismus, and increases the odds of early rebleeding 10-fold 4
• Ultraearly rebleeding risk is highest (15%) within the first 24 hours, with 70% occurring within 2 hours of initial SAH 1
• Despite high mortality (>50%), treatment should be considered as good outcomes are possible in 39-40% of treated patients, with patients >65 years still able to achieve functional independence (42% at 6-year follow-up) 5